We probably won’t learn anything about the Soul Stone until Avengers: Infinity War, but an official new prelude comic Marvel just released gives fans an ominous hint: “it could prove to be the biggest threat of them all.”

On Wednesday, Marvel released the second of its two Prelude comics that explain what the many Marvel heroes are up to leading into Infinity War. This one not only further explains Doctor Strange’s cameo in Thor: Ragnarok, but features a scene were Wong gives Strange a quick recap of every Infinity Stone in the universe. That includes everything he knows about the Soul Stone, which isn’t much.

The comic recaps everything that’s ever happened with an Infinity Stone in the MCU, which includes little flashbacks to scenes from most MCU movies. Wong talks about the Eye of Agamotto, Tesseract, Aether, Mind Stone, and Power Stone in that order.

And just as Wong is about to move on to the Soul Stone, Thor and Loki show up in New York City and derail the conversation:

As Wong explains the Infinity Stones to Doctor Strange, Thor and Loki arrive in New York City.

Once Strange sends Thor and Loki away, we finally get to the big question on everyone’s mind: What’s the deal with the Soul Stone?

It’s a cheeky meta moment when Strange says, “Can we not to that thing where you get all cryptic and instead just tell me about the last Stone?” Promptly, Wong gets “all cryptic.”

The little information that Wong has from the mystic archives remains obscured by the strange language of an ancient text, but he ominously says the Soul Stone “could prove to be the biggest threat of them all.”

In the comics, at least, the Soul Stone (there called an Infinity Gem) has the power to manipulate living and dead souls, which means the wielder can control just about anyone and potentially bring people back from the dead.

There are several prominent theories about its location, the prevailing one being that it’s somewhere in Wakanda. Black Panther didn’t reveal anything about it, but for all we know, maybe the Soul Stone is the meteor that created all that Vibranium?

The first prelude comic caught us up with Bucky, Captain America, Iron Man, and other Avengers before Infinity War. Typically, these movie tie-in comics don’t offer up much new information, but the Infinity War preludes have proven to be an enticing appetizer as we get ready for Infinity War’s May 4 premiere.